Page:The Botany of the Antarctic Voyage.djvu/320

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FLORA ANTARCTICA.
[Fuegia, the

Ottoa, H. B. K., and (Enanthe, Lamk.; indeed it is to the latter genus alone that the present is allied in the fishdose leaves, while it resembles the former in the septate structure of the foliage, and has other points of affinity in the rank smell and taste, aquatic habit, vittate mericarps, and the longitudinal ridge iu front of the seed itself.

The Falkland Island specimens are very constant in the form of their leaves ; those from the Plate River, on the other hand, are exceedingly variable both in size and foliage, the latter sometimes measuring six inches long and expanding into a plane, linear-lanceolate, obtuse lamina.

In both Americas the Crantzia is confined to the east coast ; in the northern hemisphere ranging from 30° to 42°, and in the south from 35° to 52°.

Plate C. Tig. 1, portion of a leaf; fig. 2, a flower ; fig. 3, petal; fig. 4, ovarium and styles ; fig. 5, ripe fruit; fig. 6, transverse section of the same : — all magnified.

6. OREOMTRRHIS, Endl.

1. Oreoiiyrrhis Andicola, Endlicher. Caldasia Andicola, Lagasca in DC. Mem. p. 5. t. 2. DC.Prodr. vol. iv. p. 229. Myrrhis Andicola, Humb. Bonpl. et Kunth, Nov. Gen. et Sp. Plant. Am. vol. v. p. 13. t.419. Azorella daucoides, D'Urv. Mem. Soc. Linn. Paris, vol. iv. p. 613. Gaud, in Freyc. Toy. Pot. p. 135. DC. Prodr. vol. iv. p. 77. (Tab. CI.)

Hab. Falkland Islands ; in grassy places, abundant ; Pi Urville, J. D. H.

This, which is rather a variable plant, appears to be altogether identical with that gathered on the Andes by Humboldt and Bonpland, and more lately by Linden, near the snow line on Orizaba, in Mexico, by Goudot in New Grenada, at the limit of perpetual snow, by Professor Jameson at an altitude of 14,700 feet, on the Andes of Quito, and by Mr. M'Lean in Peru : for I refer all the Caldasia of these collectors to the present species, which there, as in the Falklands, has the leaves more or less cut, their segments crowded or lax, and all the parts copiously hairy or nearly smooth. It is very singular that it should not have been hitherto found at any intermediate station between Peru and the Falkland Islands, where it grows as constantly at the level of the sea, as at the limit of eternal snow on the Cordillera under the line. Assuming 15,000 feet to be its station under the equator, it has descended that number of feet in 52 degrees, or nearly 300 feet for every degree of latitude. The labours of Humboldt and of Professor Jameson, who have determined with great accuracy the zones of elevation which many plants of the Cordillera affect, are daily proving of increased value, and now that many of the same species are fcmnd at far less elevations and even on the shores of the ocean in lower latitudes, they afford most essential data for comparing the effects of latitude with those of elevation upon vegetation, which, from various causes, are not what the difference of temperature would indicate. Thus, the parallel of the Straits of Magalhaens appears to be the point where plants, inhabiting the altitude of 15,000 feet under the equator, meet the ocean; but the snow-line itself is there 4,000 feet higher and does not descend to that level for eight degrees further south.

Plate CI. (under the name of Caldasia daucoides, Hook, fil.) Fig. 1, umbel ; fig. 2, a flower ; fig. 3, petal; fig. 4, upper portion of germen, showing the stylopodia ; fig. 5, ripe fruit ; fig. 6, transverse section of the same : — all magnified.

7. OSMORHIZA, Raf.

1. Osmorhiza Chilensis, Hook, et Am., Bot. Beechey Toy. p. 26, et in Dot. Miscel. vol. iii. p. 355. O. Berterii, DC. Prodr. vol. iv. p. 232. Scliuclia Chilensis, Molin. Chili, p. 125. Scandix clavata, Banks et Sol. MSS. Mus. Banks, cum icone. Chseropliyllum Chilense, Poir. Encycl. vol. v. p. 105.

Hab. Tierra del Fuego, Commerson ; Good Success Bay, Banks and Solander.

Also gathered by Capt. King, at Cape Fairweather, on the east coast of Patagonia ; and it is a native of Chili.